refactor(vscode-ide-companion): 重构代码并更新文件命名

- 更新文件命名规则，使用小写字母和下划线
- 修复部分代码导入路径
- 删除未使用的 WEBVIEW_PIN_FEATURE.md 文件

packages/vscode-ide-companion/src/webview/App.tsx

@@ -6,7 +6,7 @@
 
 import React, { useState, useEffect, useRef } from 'react';
 import { useVSCode } from './hooks/useVSCode.js';
-import type { Conversation } from '../storage/ConversationStore.js';
+import type { Conversation } from '../storage/conversationStore.js';
 import {
   PermissionRequest,
   type PermissionOption,